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My son had his first classroom session for his O/W cert. last night. While I was talking to the assist instructor, he mentioned that he expected safety stops to disappear soon. (As in NOT be recommended). He said that DAN had just released some research information recommending:
a. - reducing ascent rates from 30 fpm to 10 fpm and
b. - eliminate the safety stop.
I have looked on the DAN webpage and the last two issues of Alert Diver (the only two I have at the office) and can find no mention of it. Am I missing it somewhere?
Originally posted by Green_Manelishi It is *possible* that DAN has leaked the information (no pun
intended) and it has yet to appear in print anywhere for wide
distribution.
Do they release information to the agencies/instructors before the general public?
I doubt very much if DAN would make such a radical decision after so much documented benefits of a safety stop. Besides elimination of silent bubbles and offgassing, there are other reasons for the safety stop. When the safety stop got introduced, one of the main reasons for it was to slow down the divers and make them stop before continuing to the surface. Later all the tests started. But all aside, it is not DAN's position to make such decisons, they can only report findings. Before such a dicision would be made in the industry, there would be much debate and discussion before it would happen. But I doubt very much it ever will. The only thing I can see happening is renaming the safety stop to a deco stop since in reality that is what it is, a deco stop.
Originally posted by devilfish The only thing I can see happening is renaming the safety stop to a deco stop since in reality that is what it is, a deco stop.
...all dives are deco dives... time spent at increase pressure will load the tissue with nitrogen to some degree or other and many divers experience subclinical DCS without knowing why they are tired and have a feeling of general malaise... every dive should conclude with a minimum deco of 1 minute stops at 30' 20' and 10' IMO...
Slowing the ascent to 10fpm is important but if you will check back a few issues of alert diver in the editorial it is pointed out the linear slow ascent without any stops is not better than making descrete stops.... stops are a necessary component of proper decompression...
An instructor who puts out this kind of info is not being helpful. A young student might think he's getting hot inside-track info and blow off safety stops. What you've heard above is correct. DAN still recommends safety stops and probably always will. Ascent rate recommendations have gone from 60 to 30 feet per minute and there are lots of recommendations for discrete short stops periodically up from depth, as in more safety stops, not fewer or none. Skill and cunning will overcome ignorance and superstition every time, but some times it seems to take far too long. Don't fall for this armchair, between classes, BS. Go with the words printed in your manual. Incredible! Moxie
So if I go on a 20 minute dive to 60' I should take 3 minutes to ascend to 30' another minute there, then another minute to get to 20' then another minute there, then another minute to get to 10' and another minute there, and another minute to get to the surface. A grand total ascent time of nine minutes. But with the PADI system considering Im only at 60' and Im not even"
required" to do a safety stop, Im up in one minute! I think a 30' per minute ascent rate with a minute safety stop sounds like a happy medium for this dive. Mabee ascent profiles need to be assessed and agreed to by the divers involved, according to the dive profile, Keeping the recommended minimum ascent rate as a base for simple dives, and building in an increased safety factor based on the possibilitys of increased nitrogen loading.
You can find tables which show no decompression stop required limits.
The first row in the Royal Naval air decompression tables no deco stop is required.
If you are diving for fun and recreation, I think it prudent to dive to lower limits and add a safety stop.
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